1. Field of the Invention.
The present invention relates to a magnetic cleaning device which is passed through a pipeline to remove ferromagnetic debris.
2. Prior Art.
Pipelines for fluid transportation make use of pipeline equipment that is passed into and through the pipeline. The equipment may be spherical or cylindrical and may be pulled, pushed or forced through the pipeline. A spherical example is illustrated in Frederick, et al. (U.S. Pat. No. 3,546,642). The pipeline equipment may be used for gauging or inspecting the inside wall of the pipeline or for separating various fluids. In one type of pipeline pig, flexible cups are mounted on a central shaft, mandrel, or pig body with the edges of the cups engaging the internal wall of the pipeline.
Pipeline equipment for cleaning the interior of the pipeline loosens and removes material that has been deposited or that has developed. Examples of pipeline debris are rust, scale and welding rods, slag and petroleum sludge. In one type of pipeline cleaning pig, brushes engage the internal wall of the pipeline. In another type of cleaning pig, scrapers engage the internal wall of the pipeline. A magnet or magnets are used to attract ferromagnetic debris to the cleaning device and remove ferromagnetic debris from inside the pipeline. An example of this type is seen in Stephens (U.S. Pat. No. 3,292,197).
It is also known that pipeline inspection equipment utilizes magnets to produce a magnetic field. The change in the magnetic field indicates an event or anomaly to be detected. The anomaly detection is effected by the presence of magnetic debris in the line.
It is, therefore, desirable to provide a magnetic cleaning device.
It is also desirable to provide a magnetic cleaning device having magnets mounted on a flexible disc that may be attached or detached from the cleaning device as needed.
It is also desirable to provide a magnetic cleaning device having multiple magnets that may be easily inserted or removed from the flexible disc.
It is also desirable to provide a magnetic cleaning device having magnets disposed close to but not in contact with the inside walls of the pipeline.
It is also desirable to provide a magnetic cleaning device having magnets mounted on a disc that will flex when encountering irregularities in the pipeline.
It is also desirable to provide a magnetic cleaning device having magnets disposed radially with retainer plates for each magnet which secure the magnets in the circular disc.
It is also desirable to provide a magnetic cleaning device having magnets mounted on a flexible disc so that multiple flexible discs may be employed for greater magnetic debris removal.
It is also desirable to provide a flexible disc having magnets therein that may be mounted on existing pipeline cleaning devices.
It is also desirable to provide a magnetic cleaning device wherein the magnets are properly oriented for greater debris drawing and holding capabilities.
It is also desirable to provide a magnetic cleaning device for use along with a pipeline inspection device.